Microsoft Surface Modern Productivity Hub no longer working on dual monitors

Hi 

I have been using a Surface Pro 8, 16GB RAM, 256GB SSD, 13inch and connected it to:

(a) a Microsoft Surface Modern Productivity Hub with a HDMI lead connected to a monitor; and

(b) a separate Microsoft Surface Book 2 USB-C to HDMI Adaptor with a HDMI lead connected to a second monitor.

So basically I had 2 monitors connected to the Surface Pro.

This worked brilliantly for 6-7 months until a recent update on the Surface Pro and ever since the connections do not work together. Now it will only display one monitor, not two, like it used to.

Can anyone help me please to fix this as it's really frustrating and I need both monitors connected at the same time?

I don't know if there's a firmware available that I need to load? or if there's a fault somewhere?

Please help!

Many thanks